Stents are used for various therapeutic purposes within the vasculature, including opening vessels, flow diversion to limit blood flow to a problematic region such as an aneurysm, or as a scaffold to retain other therapeutic material within a target region.
Delivery of stents can be difficult for several reasons. Many stents end in a looped end configuration with a plurality of loops and most stent delivery systems must connect to one or more of these loops to deliver the stents. Stent delivery systems which hold all the loops are difficult since the stents are delivered through relatively small catheters, leaving little room for a delivery design which can grip all the loops. Delivery designs or systems which hold only one loop of the several loops are problematic since the stent is only being partially controlled during delivery. Since stents generally have shape-memory and therefore adopt their expanded shapes quickly once they are released from the delivery catheter, positioning and repositioning stents after delivery is also an issue.